Means for supplying abrasive material to drills



F. F. DAVIS Sept. 14, 1943.

MEANS FOR SUPPLYING ABRASIVE MATERIAL TO DRILLS Filed Jan. 22, 1942 0 fM 2 M M 5 e ugh I point.

Patented Sept. 14, 1943 MEANS FOR SUPPLYING ABRASIVE MATERIAL T DRILLSFrancis F. Davis, Houston, Tex. Application January 22, 1942, Serial No.427,686

'7 Claims.

This invention relates to means for supplying a drilling medium to adrill.

In drilling bores in the earth, there are oftentimes encountered veryhard materials which ordinary bits or drills will not penetrate. It hasbeen common practice for a number of years to use some type of drill andfeed an abrasive material from the top of the well, and shot iscornmonly used which is dropped from the surface of the well and musttravel down the entire length of the drill stem which may be four orfive thousand feet, or shorter, or longer. There is no way ofdetermining when the shot reaches the bit and there also is no way offeeding said shot at regular intervals so that it will be fed constantlyto the bit, as the shot must fall down through the drilling mud andoften becomes lodged in the coupling, or will still be in the process offalling down to the bit when the drill string is being pulled out of thewell.

Therefore, it is an important object of this invention to provide newand improved means for supplying drilling or abrasive material to adrill bit so that said abrasive material 'coacts with the drill indrilling.

Another object of the invention is to provide a new. and improved meanssupplying an abrasive material to a drill by centrifugal forcecontrolling the feeding of said abrasive material.

Still another object of the invention is to provide an improved meansfor supplying an abrasive material to a drill bit, and said supplyingmeans capable of being placed at any desirable A construction designedto carry out the invention will be hereinafter described, together withother features of the invention.

The invention will be more readily understood from a reading of thefollowing specification and by reference to the accompanying drawing, inwhich an example of the invention is shown, and

wherein:

Figure l is a vertical view, partly in section and partly in elevation,showing one means for carrying out this invention,

Figure 2 is a vertical view, partly in section and partly in elevation,showing another means for carrying out this invention,

Figure 3 is an enlarged fragmentary view in section, showing the feedingmeans, constructed in accordance with the invention, in its closedposition, and

Figure 4 is a view similar to Figure 3, showing the feeding means in itsopened position.

In the drawing, the numeral ill designates a drill pipe. Suspended onthe lower end of the drill pipe i0 is a shot feeding mechanism ii, and

suspended on the lower end of said shot feed is a core drill l2. Thecore drill I2 is one that is commonly used where the shot is fed fromthe surface of the well. As may be seen in the drawing, the drill isprovided with an enlarged drilling-head I! which has an inwardly anddownwardly directed slanting shoulder ll provided on its inner surface.

A plurality of longitudinal grooves I are also provided on the innercircumference of the head l3 so as to allow the shot to travel down pastthe core and prevent the shot from becoming lodged between the core anddrilling head. However, it is pointed out that said shot is free to passbetween the core and the inner'circumference of the head. The grooves llalso are provided so that the drilling fluid or mud may pass downthrough the drilling head and around the core. Provided in the lowerportion of said drilling head are a plurality of slots L5 (as shown inFigure 2), or what are commonly termed shot heels," which allowcirculation, and also allow the shot or abrasive material to get undersaid bit. The upper end of the core driller is connected to a collar i8which is provided with an axial bore I'I extending therethrough.

An upstanding collar i8 is shown mounted on top of the collar l6, andthis collar ll may or may not be employed; the principle being that theshot which escapes from the bottom of the drilling head will be carriedup the well bore by the drilling fluid. and after it passes the upperend of the collar ii, the mud will lose some of its velocity and theshot will fall out and fall into the collar II. This is common practiceand has been used for some time; but, as pointed out, this collar l8 maybe employed or left off. It is further pointed out that any type.of bitmay be suspended from the collar i6 and is not necessarily limited to acore drill.

The upper end of the axial bore of the collar I6 is internallyscrew-threaded and receives a pipe i9, said pipe being connected to thelower end of the shot feed or the feedfor the abrasive material. Theshot feed includes a hollow cylin- -pipe II. As may be seen in thedrawing, said 30 within the housing 20 and surrounding the pipe 25. Asmay be seen from the drawing, the fluid or drilling mud from thedrilling pipe II is free to flow through the housing 20, the pipe I! andthe collar I8, to the bit l2.

On the upper end of the head 24 there is provided a screw-threadedopening and plug 3| so that the chamber 30 may be filled with a suitableabrasive material, such as chilled shot. An opening I! is provided inthe flange II at a point adjacent the pipe 2! so that the abrasive ma'--terial which has been placed in the chamber 3! may flow through saidopening. -.To close theopenin there is provided ordinary flap valvenecessary, the plug "of the housing 20 removed and more shot poured intothe chamber 30, and the device again run into the well. This operationis repeated until the desired orienting is completed.

In Figure 2, there is shown another means for ca y ng out this method.In this form the core drill I 2 is identical to that shown in Figure 1,except that it is connected to an internal collar instead of to thecollar i8. Connected to the upper end oi the collar II is an elongatedbell 38 which is connected to a collar 31 having an axial bore 38therethrough, To. the upper end of the collar 31, thedrill pipe" issuitably con nected. g l

The lower portion of the axial bore 30 of the collar 81 receives ahollow pipe 39, which extends downwardly into the bell It and hasaflh'ousin 40 connected to .the lower end thereof. The housing 40 isprovided with conical-shaped ends 4| and 42 which may be of any desiredlength.

- The end 4| is suitably connected to the lower end of the pi 38, andsaid pipe is provided with slots 43 so that drilling fluid ,or gravel,such as II which has a weighted arm I4 connected there -p to. The weight34 will hold the flap valve-l8 in the position shown in Figure lwhenthepipe'or the housing is not rotated; but, upon'rot'atiom' theweight It will swing outwardly awaygfrom,

the central axis of the housingythei'ebyimoving the valve it away fromthe opening}! and the shot or abrasive material to dron-throuh theopening 32. When.the rotationfoffthepipe,

or housing is stopped, the weight jl'w'ill again swing the valve ll backagainstthe flange, as

shown in Figure andno moreabrasive i iue rm y iiow therefrom.*Therefore, a maybe seen from the drawings, the shot or abrasive-mmterial is at. a point in close proximity to thei drill,v bit and theshot is fed'continuoualyand atan.

even rate of flow while the pipe or housing is rotated, but the flow ofthe abrasiveimaterial is shut oil immediately upon rotation of thehousing 20.

the stopping ofthe H described in Figure 1, may flow down through thepipe ill and pipe 3!, and out through the slots- Thus, the housing 40does not interfere with the normal flow of drilling fluidor the use 7oi' gravel when desired. As may be seen from the The chamber It may bemade any desirable and suitable length so as to hold as much abrasivematerial as desired by. the user. Further, the chamber ill and thehousing 20 maybeplaced at any suitable point and is not limited to beingplaced in close proximity .to the drill bit.

In the use of the device shown in Figure l, the drill pipe is made upwith the core drill i2 and the shot feed or abrasive feeding device i Isuspended on the lowerend thereof, while it is being run into the bore.has been filled through the plug 3i before it is inserted into the boreand when the bottom-has been reached, the pipe is rotated. This rotationwill open the valve 33 and allow the shot or abrasive material tocommence feeding to the, drill It.

Naturally, the chamber Ill drawing, there is no strain placed upon theshot or abrasive feeder, and therefore it may be made of a lighter'metalthan that shown in Figure l.

. The lower end 42 of the housing is provided with an opening 44 whichis closed by a flap valve ll constructedsimilarly to the flap valveshown in Figure 1. Also provided on the end 42 is a screw-threadedopening and plug 48 through which the chamber within the housing 40 isfilled with a suitable abrasive material.

In the operation, this form functions similarly to the form shown inFigure 1, that is, when thetdevice is in the bore and rotation isstarted, the flap valve I will open, allowing the abrasive material tofeed out through the opening It, and'down to the core drill, and thedrilling fluid may flow out through the slots 43, down to the coredrill. In removing the core, gravel may also flow through ,the slots l3and lodge upon the inclined shoulder, thereby holding the core so thatit may be removed from the What I claim and desire to secure by Letters.Patent is:'

1. An abrasive feeding device for a rotary drilling mechanism having adrill member at its When it is desired to retrieve the core cut, the

ordinary procedure is to drop gravel or a similar substance down throughthe drill pipe ill which will travel down through the pipe 25, the pipe[9 and the collar [8, to the bit, and will lodge upon the inclinedshoulder ll, the core in the core drill. Thus, bypulling upwardly, thecore is broken oil and is held within the core drill by the gravel orsimilar substance until it has.reached the surface. At that time thecore drill is unscrewed from the collar l6 and the core removed from thecore drill and then the core drill replaced on the collar I 6 and, ii

thereby wedging passage communicating with the member including, areservoir disposed within the drilling mechanism above said member forreceiving an abrasive material, the reservoir havingcentrifugally-aotuated closure means for normally preventing the'escapeof the abrasive material therefrom, whereby the closure means is openedto feed said abrasive material from said reservoir to the drill memberupon rotation of said drilling mechanism and is closed upon cessation'ofrotation of the mechanism.

2. An abrasive feeding device as set forth in claim 1 wherein theclosure means of the reservoir is pivotally supported.

8. An abrasive feeding device as set forth in claim 1 wherein theclosure means of the reservoir includes a closure portion and a weightportion adapted to be actuated by centrifugal action, whereby the weightportion will be swung outwardly upon rotation of the drillingmechportion away from abrasive anism to move the closure said reservoirto permit feeding of the material to the drill member.

4. An abrasive feeding device as set forth in claim 1 wherein theclosure means of the reservoir includes a pivotally-mounted member witha weight depending therefrom adapted to be actuated by centrifugalaction.

5. An abrasive feeding device as set forth in claim 1 wherein thereservoir ha a discharge opening in its lower portion, the closure meansincluding an angular pivotally-mounted memher having a flap valve fornormally closing the discharge opening of said reservoir and a weightedarm for normally holding the flap valve in its closed position, theweighted arm being actuated by centrifugal action to swing said flap-FRANCIS F. DAVIS;

